Detailed information about drought in southwest China.

Yunnan, Guizhou, Guangxi, Sichuan and Chongqing are the worst droughts in a century. The dry weather in some places can be traced back to July 2009. In March, the drought spread to Guangdong, Hunan and the Mekong River Basin in Southeast Asia. As of March 30th, the drought-affected area of cultivated land in China was 1. 1.6 million mu, including 90.68 million mu of crops, 2.85 1.5 million mu of severe drought and 0/.5 million mu of dry land. The cultivated land to be sown is short of water and moisture. There are 24.25 million people and15.84 million large livestock who have difficulties in drinking water due to drought. [1] Yunnan, Guizhou, Guangxi, Chongqing, Sichuan and other five drought-stricken provinces (autonomous regions and municipalities) have invested a total of 465,438+1000000 yuan, invested 25.26 million workers, invested1kloc-0/40000 sets of drought-resistant mobile equipment, and sent water trucks.

cause

Meteorological perspective

Ren Fumin, chief expert of the National Climate Center, said that this was the worst drought in southwest China since meteorological data were available. Drought is a combination of less precipitation and high temperature, which lasts for a long time [2].

According to Ren Fumin, the climate in southwest China, such as Yunnan and Guizhou, is characterized by clear rainy season and dry season. There was little precipitation in the rainy season last year, and it gradually stopped after August, which is equivalent to the early end of the rainy season. After that, there has been less precipitation. Compared with the same period in history, Yunnan and Guizhou have the least history.

On the contrary, in these 200 days, the average temperature is 65438 0 to 2℃. Compared with the same period in history, Yunnan has the highest temperature and Guizhou ranks third.

Jiao, deputy director of China Meteorological Bureau, said in online communication with netizens that since the beginning of 2000, Yunnan-Guizhou area has been under the background of less precipitation and higher temperature. This year, it should be said that the drought is more serious under the background of less continuous precipitation and higher temperature in recent years.

Climatological viewpoint

With global warming, the El Ni? o phenomenon in the Pacific Ocean intensifies, destroying the atmospheric structure, causing the ocean monsoon to fail to land and form rainfall. From the atmospheric circulation situation, since the winter, the south branch trough is weak, and the warm and humid airflow from the southwest of the Indian Ocean is weak, resulting in insufficient water vapor supply. In addition, the response of the southern climate to El Ni? o phenomenon is lagging behind, and meteorological drought is prone to occur in the southwest.

"It can be said that the increase in the frequency and intensity of extreme weather is caused by global climate change." Wang Xuefeng said that not only drought, but also all kinds of extreme weather. For example, extreme abnormal weather such as "heavy snow in the north, drought in the south" appears more and more frequently in China.

Ma Zhenfeng, a climate expert and director of Sichuan Climate Center, explained this year's "drought" in detail from the perspective of climatology.

First, the plateau thermal factors of the Qinghai-Tibet Plateau. Sichuan Province is greatly influenced by the "roof of the world". Last winter, there was little snow on the Qinghai-Tibet Plateau, and the plateau thermal factors were good, which affected the drought.

The second is the influence of El Nino phenomenon. Under this influence, the surface heat flow in the Pacific Ocean moved eastward, taking away tropical vapour band, which led to an increase in precipitation in eastern China. On the contrary, tropical water vapor decreases, and less water vapor enters the southwest from the south.

Third, the timing of cold air is not well grasped. Although the cold air has affected China many times this winter, most of the cold air began to move eastward in the north and directly "slipped" from the edge of Sichuan Province. Coupled with the Qinling Mountains, if the cold air is not "strong" enough to cross the mountains, it will still not affect the basin. Even if sometimes cold air enters the basin and forms the first condition of rainfall with warm air: convective weather, the second condition of rainfall cannot form precipitation without rich water vapor. "This is a process that requires cooperation."

According to the global climate report of GBN, the climate in China in 20 10 will cause severe drought in southern China around 20 10. At present, the precipitation distribution pattern of "waterlogging in the south and drought in the north" in China may become "waterlogging in the north and drought in the south", but experts have analyzed that the current drought has little to do with it.

Insufficient construction of water conservancy facilities

Guizhou is not short of water. Due to historical reasons such as natural conditions and insufficient investment, there are only 34 medium-sized reservoirs in the 17893 water storage project completed in Guizhou Province, of which 99.9% are small reservoirs with a total storage capacity of less than 2 billion cubic meters, so the drought resistance is naturally weak.

Small reservoirs in Yunnan have hardly been repaired. At present, there are14 villages and towns in Yunnan with difficulty in drinking water. Some local reservoirs, smaller than small ones, not only lack repair funds, but also have no corresponding scientific management, which leads to their depletion faster than small reservoirs in drought.

[Edit this paragraph] Impact

Water source reduction

Some reservoirs dried up because of drought, and some rivers dried up until they were cut off. By March of 20 10, the water level in the upper reaches of the Yangtze River had also dropped significantly. For example, the current flow of Huangguoshu Waterfall has been reduced to the lowest level in history. Every day, only 10 releases a small amount of water for tourists to watch from morning to 4 pm, and the rest 18 hours are cut off. Huangguoshu Waterfall with a width of 100 meters reduces crop yield and affects spring ploughing and sowing.

At present, it is a foregone conclusion that the drought in southwest China affects spring ploughing and spring sowing, and the drought will not be fundamentally alleviated until at least late May. Due to the poor harvest, some arid areas in Yunnan are facing a ration crisis.

The prices of agricultural products have risen locally.

It is reported that rice prices in Shanghai, Chongqing, Yunnan and other places have risen for a short time. [3]

The price of flowers has gone up. Yunnan suffered a hundred years of drought, and Yunnan's flowers were reduced in large areas. At the same time, the total price of cloud flowers did not increase because of the scarcity, but decreased. The reason for this "abnormal" state is the decline of cloud quality. The double decline in the quantity and quality of clouds has also caused a large-scale increase in the price of flowers nationwide.

60% of the country's hydropower is in an emergency.

The drought in the southwest disaster area continued, some hydropower units almost stopped production, and the hydropower generation in various places was much lower than the same period in history. The power generation capacity of China Southern Power Grid has dropped sharply, and there is a shortage of electricity in various places, which has caused difficulties for people's lives and drought resistance. The inventory of some power plants in Sichuan has been below the 7-day warning line, and the drought in Guangxi has caused 90% of hydropower to be "paralyzed". The drought in southwest China has caused 60% of the country's hydropower emergency, and many thermal power units are struggling. [4]

[Edit this paragraph] Drought in various places

Yunnan province

Yunnan Province is one of the areas with the worst drought, with agricultural losses as high as 65.438+0.72 billion yuan, and 600,000 mu of rape flowers in Luoping, Yunnan Province have turned into a dead sea. 600,000 mu of rape flowers in Luoping turned into the Dead Sea.

The continuous drought in Yunnan in recent three seasons has caused drinking water difficulties for 7.8 million people and 4.86 million livestock. Crops sown in autumn and winter failed to harvest 1.4 1.7 million mu, and the grain output of Koharu province decreased by more than 50% compared with the previous year.

Guizhou Province

Since the autumn of 2009, there has been almost no rainfall in most parts of Guizhou Province.

By March of 20 10, 84 counties and cities in Guizhou province were affected, and the affected population170,000 people, more than 5 million people and more than 2 million livestock had difficulty drinking water, and urban industrial water use was almost at a standstill.

By April of 20 10, the drought-affected area of crops in Guiyang reached 784,400 mu, including 498,450 mu of light drought, 2510.73 million mu of heavy drought, 34,890 mu of dry land, water shortage in paddy field10.27 million mu, and water shortage in dry land/. Twenty-nine small reservoirs and 6 19 small mountain ponds in the city have dried up, and nearly 70% of the reservoirs have fallen to the dead water level. Due to drought, 422,482 people and 237,496 large livestock have temporary drinking water difficulties. According to the statistics of agricultural department in Guiyang, there are 425 drought-affected farming enterprises, farming communities and large-scale farms (households) in the city.

Sichuan Province

According to the Sichuan Provincial Department of Agriculture, the drought has affected more than 6 million mu of crops in the province. As of March, 20 10 and 16, the spring crops in this province suffered from drought of 5170,000 mu, with severe drought of 780,000 mu, of which nearly 400,000 mu of crops planted in Panzhihua, the hardest hit area, suffered from drought, and108,000 mu of crops failed to harvest.

Guangxi

The continuous dry weather has led to the rapid development of drought in Guangxi. In Guangxi 14 prefecture-level cities, drought has occurred in 13, and the drought in western Guangxi has further aggravated and spread to the central and eastern regions. At present, the drought level in Guangxi has reached severe drought, especially in northwest Guangxi. Recently, high temperature and lack of rain have caused the rapid spread of drought in Guangxi, and the drought in northwest Guangxi has further aggravated.

As of March 18, the drought-affected area of crops in Guangxi was11263,800 mu, including 7,338,400 mu of light drought, 3,585,200 mu of heavy drought and 340,200 mu of drought. The water shortage in paddy field is 2.2765 million mu, and that in dry land is 5.086438+0.7 million mu. Due to drought, 218120,000 people,1170,000 large livestock have difficulty drinking water, including 886,000 people in Baise city and 697,600 people in Hechi city. The number of people who need water supply to solve the drinking water problem is 3 18600, including Baise 188900 and Hechi 129700.

As the water level of Lijiang River in Guilin continued to drop, Guilin adjusted the tour route of Lijiang River on March 16, and the adjusted route was shortened by more than half compared with the original tour route, and the fare was also lowered by 1/3. At present, the affected area of crops in Guangxi is more than 6.5438+million mu, rice seedling raising and crop sowing are seriously affected, and the situation of spring ploughing production is even more severe.

Chongqing

Since March 15, moderate rain has fallen in central Chongqing and other areas, which has improved soil moisture and eased the drought. However, the water storage of the project has not been effectively supplemented, and drinking water for people and animals in some areas is still difficult.

[Edit this paragraph] Disaster relief

According to the latest statistics of the National Defense General, as of March 3 1, Yunnan, Guizhou, Guangxi, Chongqing, Sichuan and other five drought-stricken provinces (autonomous regions and municipalities) have invested a total of 41.1.40 billion yuan in drought-resistant funds, 25.26 million laborers and drought-resistant mobile equipment. The Prime Minister visited the arid area

It is reported that at present, the drought-affected area of cultivated land in China is 1. 1.6 million mu, of which 5 provinces (autonomous regions and municipalities) in southwest China are 97 1.6 million mu, accounting for 84% of the country's total. The number of people killed by drought is 1.93 million, and the number of large livestock drinking water is/kloc-.

The central government has allocated 654.38+0.55 billion yuan for extra-large drought relief, 800 million yuan for comprehensive drought relief in the near future, and 6.4 billion yuan for rural drinking water safety and reinforcement of dangerous reservoirs in advance. At present, there are 4,307 drought-resistant emergency water diversion projects, 70,000 "five small" water conservancy projects, more than 20,000 kilometers of water pipelines and 0.8 million new drought-resistant water source wells, providing 94 1 10,000 tons of water for the people.

According to statistics, 3.44 million people use the reservoir water supply and drinking water, 26.5438 million people implement emergency water transfer and drinking water, 940,000 people dig wells to drink water, 5.06 million people pull water to drink water, and 7.85 million people carry livestock to drink water, looking for new sources of drinking water.

[Edit this paragraph] Status quo

The Central Meteorological Observatory predicted yesterday that there will be a weak rainfall process from March 3/kloc-0 to April 2, with the rainfall generally less than 3-5 mm, of which the rainfall in the northeast of Guizhou is generally 15-30 mm. After that, there will be no obvious rainfall in most major meteorological arid areas such as Yunnan, southern Sichuan, southwestern Guizhou and northwestern Guangxi, and the meteorological drought will continue.

In recent days, there has been light rain in the arid area of southwest China, which can partially alleviate the drought. However, the drought in southwest China will not be alleviated until at least late May.

Southwest China is currently in the dry season and will not enter the flood season until the end of May. Historical meteorological data show that during the seven-month period from1October 20th1May 20th last year, the precipitation in southwest China only accounted for 14% of the annual precipitation, while during the five-month period from the end of May to 10, the precipitation in southwest China accounted for 86% of the annual precipitation. Only in the flood season will drought occur.